JPH01250918A - Endoscope - Google Patents

Abstract

PURPOSE:To automatically adjust the lightness of an image on a display screen to a state easily viewed even if an image pickup condition is variously changed by correcting a new video signal by the video signal before a previous frame in such a case that the lightness adjustment of the image can not be automatically executed only by controlling the illuminating light quantity of a light source. CONSTITUTION:When a reflected light quantity from an interest area is extremely decreased, an addition switching circuit 12 is switched by an addition switching control signal outputted from an addition decision circuit 13 to the addition switching circuit 12; therefore, a memory output from a frame memory 11 is made to be 1/2 value through a 1/2 subtraction circuit and a data selecting circuit 18, and is made to feed back to the addition switching circuit 12. Consequently, a value, which is added the memory content before the previous frame and the data of the new video signal by means of a feedback circuit constituting of the addition switching circuit 12, the frame memory 11 and the 1/2 subtraction circuit 17 and the data selecting circuit 18, becomes an actural memory output of the frame memory 11, then the new video signal is corrected. Thus, the lightness of the image on the display screen surface is automatically adjusted to the state easily watched.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention provides an endoscopic #fE device that photographs the inside of a body cavity of a subject while illuminating it, and displays the photographed content as an image on a display screen. In particular, the present invention relates to improvements in technology for controlling the brightness of a display screen by processing video signals.

(Prior Art) Conventionally, this type of endoscopic device images the inside of a subject's body cavity using a solid-state imaging probe disposed at the distal end of an endoscope, and the image obtained by this imaging. signal A
/D conversion and sequentially stored in the image memory, and based on the image data in the image memory, display a moving image or still image on a display screen such as OR1, and adjust the amount of illumination light from the light source according to the level of the video signal. A lζ electronic endoscope device with a control configuration has been proposed and is in practical use.

In the case of such a conventional endoscope device, the endoscope step: 1
- Under conditions in which the amount of reflected light from the region of interest received by the imaging surface of the monitor changes within a predetermined constant range, the intensity of light from the light source and the irradiation time can be controlled to display images on the display screen. The brightness of the image is automatically adjusted to make it easier to see.

However, when the amount of reflected light received by the imaging surface of the endoscope scope becomes extremely small, it may become impossible to automatically adjust the brightness of the image on the display screen.

(Problem to be Solved by the Invention) In other words, in the case of conventional endoscope devices, the distance between the region of interest in the body cavity of the subject and the imaging surface of the endoscope is large. If the amount of reflected light received by the imaging surface becomes extremely small, the level of the video signal will remain at low -F and will not be raised even if the light intensity and irradiation time of the light source are maximized. ,.

Therefore, image creation processing is performed based on this degraded video signal, and the image represented by the processing result is displayed on the display screen.

Therefore, conventionally, there has been a problem in that a dark area may appear on the display screen during an endoscopic examination.

The present invention has been made in view of the above problems, and its purpose is to provide a range in which the brightness of an image on a display screen is always automatically adjusted to suit the viewing and viewing conditions when the imaging conditions are variously changed. An object of the present invention is to provide an endoscope device that can be expanded.

[Structure of the invention]

(Means for solving and overcoming the problem) In order to achieve the above object, the present invention provides, in addition to means for controlling the amount of illumination light from a light source according to changes in the level of a video signal.
When the level of the video signal is not improved even if the amount of illumination light from the light source reaches a preset amount of light, the display screen 1. Each time the signal level determining means determines the value at which a dark area is formed, a determination result indicating that a dark area is formed is obtained, and the processing result of the image creation process is accepted and the video signal of the previous frame is calculated from the image. The gist of the present invention is to include a video signal correction means for correcting a new video signal obtained by the previous imaging with the endoscope.

(Function) Family celebration according to the present invention! Jl: If the brightness of the image cannot be automatically adjusted just by controlling the amount of illumination from the light source, the new video signal is corrected by the video signal from before the previous frame, and the new video signal is , which can improve the level of.

Therefore, even if the imaging conditions are variously changed, the brightness of the image on the display screen will be automatically adjusted to the bright or covered state.

(Example) FIG. 2 is a block diagram schematically showing an entire endoscope apparatus to which the present invention is applied.

The endoscope apparatus of this embodiment consists of an endoscope 1 and the entire apparatus 2. The endoscope 1 transmits light emitted from a light source 3 of an apparatus main body 2 to a distal end 4a of a scope 4 through a phytoguide 5.
A solid-state imager (CC) installed at the tip 4a of the scope 4 illuminates the body cavity (not shown) of the subject.
D) Image the region of interest in the body cavity (B) at step 6, convert the obtained electric signal into a video signal at camera control units 1 to (CCU) 7, and send this video signal to the device main body 2. I'm here.

In addition to the light source 3, the device body 2 includes a light source control section 8 that controls the light intensity and irradiation time of the upcoming fishing 3, and a light source control section 8 that issues a light intensity control command to the light source control section 8. It includes a signal processing main body section 9 that adds signals and performs image creation processing. .

The signal processing main unit 9 is the center of the present invention, and as shown in FIG.
Also, this addition switching circuit 12 switches the output data of the frame memory 11 to the 1/2 selection circuit 17 and the arter selection when the content indicated by the addition switching control signal from the addition determination circuit 13 is not in a standard state, which will be described later. It is assumed that the signal is fed back through the circuit 18.

The addition determination circuit 13 receives a light amount control signal from the video signal level detection circuit 14 obtained from the conversion data of the A/D converter 10 and a light amount control signal from the light source control section 8 to the light source 3 shown in FIG. indicates that is the upper limit? When the I-1 limit confirmation number is received, the number is added to the addition/0 switching control A and the switching circuit 12
It is said that it will be sent to.

That is, when the illumination light source of the light source 3 reaches a preset light intensity and the maximum light intensity signal of the video signal level detection circuit 14 remains low, the addition/zero determination circuit 13 determines that the condition is not standard. In other words, a TV monitor 15 such as a CRT
It is determined that a dark area is formed on the display screen of
An addition switching circuit (ri) for switching the addition switching circuit 12
This will output the number.

Further, addition switching control (P number) sent from the crimping judgment circuit 13 to the addition switching logic circuit 12 is added to the frame HI number circuit 19, and the addition switching control signal is sent to the addition switching circuit 12 in the frame HI number circuit 19. The data selection circuit 18 is operated according to the identification result.

As a result, the data selection circuit 18 allows the memory output of the frame memory 11 to pass through the 1/2 division circuit 17 only during one frame period immediately after the addition switching control signal is sent to the addition switching circuit 12. The configuration is such that data is selected to form a loop that feeds back directly to 12.

In other words, in the first addition of the addition switching circuit, the 1/2 division circuit 17 performs 1/1 division (through data).
The relationship is operated as follows.

With the configuration of the embodiment of the present invention including these parts, in the standard state in which the amount of reflected light from the region of interest received by the CCD 6 of the endoscope 2 is changed within a predetermined constant range, the endoscope The video signal from CCU 7 of 1 is sent to A/D converter 10.
After being digitized, it is sequentially stored as it is in the frame memory 1, and the memory output of this frame memory 11 is converted into a D/A.
Through converter 16 -[V monitor 15 is applied. Therefore, under the condition that only the light amount control of the light source 3 is performed, a moving image or a still image is displayed on the display screen of the monitor 15 based on the image data of the frame memory 11. Based on the conversion data of the D converter 10, the signal level of the video signal is detected in the video signal level detection circuit 14, and the light source control unit 8 controls the light intensity increase/decrease of the light source 3 to correspond to this signal level. It will be done.

On the other hand, the region of interest in the body cavity of the subject and the CCD 6 of the endoscope 1
If the distance from the image pickup surface of the CCD 6 is too far, etc.
When the amount of reflected light from the region of interest received by
2 is switched, the memory output of the frame memory 11 is changed to 1/2 via the 1/2 division circuit and the data selection circuit 18.
is fed back to the addition switching circuit 12.

Therefore, the feedback circuit consisting of the addition switching circuit 12, the frame memory 11, the 1/2 division circuit 17, and the data selection circuit 18 allows the value obtained by adding the memory contents of the previous frame and the data of the new video signal to be the actual value. A memory output from the frame memory 11 is output, and this memory output is applied to the TV monitor 15 through the D/A converter 16.

Therefore, a moving image or a still image is displayed on the display screen of the TV monitor 15 under conditions in which the new video signal is corrected by the video signal of one frame before, and the gain is doubled and the S/N is doubled. .

Note that when the new video image L is corrected using the video signal from the previous frame, the video signal level detection circuit 14 outputs a control signal to increase the light intensity, and the light source control unit 8 increases the light intensity to the maximum. The amount of light is controlled by outputting a signal.

(Effects of the Invention) As explained above, inside the endoscope to which the present invention is applied,
If it is not possible to automatically adjust the brightness of the image to a state that is difficult to see just by controlling the light intensity of the light source, the new video signal is corrected by the video signal from the previous frame, so the imaging conditions may change in various ways. The advantage is that the brightness of the image on the display screen is automatically adjusted to make it easier to see.

[Brief explanation of the drawing]

FIG. 1 is a block diagram schematically showing the configuration of essential parts of an embodiment of a TS endoscope apparatus to which the present invention is applied, and FIG. 2 is a block diagram schematically showing the overall configuration of the endoscope apparatus.

Claims (1)

[Claims] (1) An endoscope that captures images while illuminating the inside of the subject's body cavity with light emitted from a light source, and an image creation process based on the video signal obtained by imaging with this endoscope. An endoscope apparatus comprising a device main body that displays an image representing a result on a display screen and controls the amount of illumination light of the light source according to a change in the level of the video signal, wherein the amount of illumination light of the light source is set in advance. a signal level determining means for determining that a dark area will be formed on the display screen when the level of the video signal is not improved even when a certain amount of light has been reached; Every time a result is obtained, a video signal from the previous frame is extracted from the image indicated by the processing result of the image creation process, and a new image obtained by photographing with the endoscope using the video signal from the previous frame is extracted. An endoscope apparatus comprising: a video signal correction means for correcting a video signal, which is included as a component of the apparatus main body.